Pneumatic circuit breaker



Nov. 7, 1950 I B. M. H. P. FERNIE R 2,529,145

PNEUMATIC CIRCUIT BREAKER Y Fild Oct. 50, 1945 Patented Nov. 7, 950

PNEUMATIC CIRCUIT BREAKER I Bernard Marie Hilaire Paul Fernier, Lyon, France,

assignor to Ateliers de Constructions Electriques de Belle,

Societe Anonyme,

Paris,

France, a corporation of France Application October 30, 1945, Serial No. 625,563

I In Luxemburg July 27, 1939 Section 1, Public Law 690, August s, 1946 Patent expires July 27, 1959 This invention relates to pneumatic circuit breakers, and more particularly to" those provided with an auxiliary electrode in the path of the arc.

One of the objects of the present invention and objects will be readily understood from the following description, taken in connection with the accompanying drawing, showing one embodiment of the invention herein given for illustrative purposes, the true scope of the present invention being more particularly pointed out in the appended claims.

In the drawing:

Fig. 1 shows, partly in in section, one embodiment of the invention ing the first stage of its operation;

Fig. 2 is similar to Fig. -lbut shows the during another staged the operation;

Fig. 3 is a cross-section of the'embodiment shown in Figs. 1 and 2 and illustrating more particularly the relatively movable arc-drawing con tacts I and 2 and the auxiliary contact 4, on a somewhat enlarged scale. In the embodiment of the invention shown, the circuit breaker comprises two relatively movable arc-drawing contacts I and 2, the former being fixed and the other movable, and an auxiliary contact 4 which is fixed and located in the axis of this movable contact, the latter being elevation and partly dur parts tubular to receive this auxiliary contact and being provided with a longitudinal slot 3 for the passage of the stem of the auxiliary contact to enable the movable contact 2 to effect its stroke. The blow-out chamber'is shown at 5 and is provided in two opposite walls with two 13 Claims. (Cl. 200-448) opposed nozzles 5 and 1 through which the movat their end portions than at their center portions; As shown, the auxiliary contact 4 is elongated and its ends extend into the nozzles Band 1. The nozzles 6 and 'l are 'venturi nozzles hav ing restricted throats and, as shown, the ends of auxiliary contact 4 preferably terminate respectively at these restricted throats. A resistance 8 is connected on the one hand to the fixed contact I and on the other hand to the auxiliary electrode 4. The fluid or gas'for the blastis supplied to the blow-out chamber 5 through a passage 9 opening into the space separating the nozzles B and l, and substantially at right angles to the axis of the'latter. The walls or" this passage 9 may support said blow-out chamber. I The operation is as follows. As the movable contact 2 is retracted, an arc is struck between it and the'fixed contact I and is drawn out. soon-as the are thus drawn reaches the level of the upper part of the'auxiliary electrode ,4,

it attaches itself to the latter. The part or said.

are extending between said" auxiliary electrode 4 and'the nxed contact lwill thus be shunted by the resistance 8 and blown with great Iorce by the blast fluid blown out through said nozzle 6. This are being thus extinguished, the resistance 8 is thrown into the circuit. The movable contact 2 continuing its stroke, a second arc will be struck between the lower portion of the auxiliary contact 4 and the movable contact 2, but the strength of the current having been greatly diminished by the throwing into the circuit of the resistance 8, this second are will be readily extinguished .by the blast fluid or gas blown out through said nozzle 1. Movement of the movable contact 2 may be effected by any suitable mechanism of conven: tional construction heretofore used in circuit breakers. I v v f The fixed contact I may, and preferably will be, mounted so as tocushion the-impact of con-.- tact 2 upon contact I, thisv mounting herein comprising relatively slidin telescoping sleeves ll, l2 and interposing spring [3, as illustrated in Fig. 3, which shows upon an enlarged scale the relative positions of the contacts I and 2,

two nozzles 6 and 1,,theinnersurfaces of which the auxiliary electrode 4 and the nozzles 6 and I. It will be apparent that the relative mobility of the arc-drawing contacts could be realized by making both contacts movable, one after the other for example, and that capaoity means could be substituted for the resistance, or "inductive means could be substituted, or such alternative means could be connected in parallel with the resistance.

Circuit breakers embodying the present invention possess many advantages over those heretofore used, moreparticularly as regards the perfect safety w1th which the resistance is inserted in the circuit of the arc, and the severance of the second arc in series with said resistance; this safety is assured by the perfect separation of the two arcs and by thefact that each of the arcs is blown out by an appropriate nozzle. Furthermore, no part of the arc enters the pressure chamber, thus avoiding great constraint of the arc and the creation of excessive voltages at the moment of the rupture of the arc; addition, the blow-out fiuid or gas is used to better advantage as the arc does not affect it and does not impede its exhaust.

I am aware that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and I therefore desire that thepr'fse'nt embodiment of the invention b'e considered in all respects as illustrative andnot' restrictive, reference being had to the appended "claims rather than to the foregoing description to indicate the scope of the'inventio'n'."

I claim:

1. In a circuit breaker with pneumatic blow-- out, a principal fixed electrode, 'a movable elongated electrode having a contact end, means for'moving said movable electrode and its contact end axially thereof away from andtowar'cl said fixed electrode, a closed blow-out "chamber hav: 'ing two spaced opposite walls'which are electrically insulating, said chamberl'being "interposed in the path of "the Contact e'hdpf s'aid movable electrode between theextremeclo'sed and open positions thereof,said chamber being provided with two" nozzle'opening's respectively in said opposite wallsf thereof 'an'daligned axially in the p'athof saidf"'niovable elec't'rodd'tlierethrough and providinga"clearance "around said movable electrode, and a separate auxiuary'eiectrode fixedly 'carried'by'said chamberin afposition intermediate and 'extendingbetweeriand spaced from said opposite walls thereofand close to butspace'd fromsai d'movable "electrode during its passage through said chamber, said movable electrode andauxiliaryelectrodeibeing so "constructed as to permit the movement of said movable electrode past' said-auxiliary electrode'with narrow clearancetherefrom;

2. In a circuit breaker with-pneumatic blowout, a principal fixed electr'odeya movable elongated electrode having a cont-act end, means-for moving said movable electrode and 'its'contact end axially thereof away from and toward said fixed electrode, a closed blow-out chamber hav-' ing two spaced opposite walls which are electrically insulating, said; chamber being interposed in the path of the' contact end of said movable electrode between the extreme closed. and open positions thereof, said chamber :being provided with two nozzle openings respectively in said opposite walls thereof and alined axially in the path of said: movable electrode therethrough and providing a clearance around said movable electrode, and a separate auxiliary elec;

trode fixedly carried by said chamber in a position intermediate and extending between and spaced from said opposite walls thereof; and.

' moving said movable electrode and its contact end axially thereof away from and toward said fixed electrode, a closed blow-out chamber having two spaced opposite walls which are electrically insulating, said chamber being interposed in the path of the contact end of said moyable electrode between the extreme closed and open positions thereof, said chamber being provided with twonozzle openings respectively in said opposite walls thereof and alined axially in the path of said movable electrode therethrough and providin 'a clearance around said movable electrode, said movable electrode being tubular, ma a, separateelcng'ated 'r'o'deshaped auxiliary 1 ctr9 fixedly carried "by'Tsai' chamber in a position within the bore Qf..said tubular movable electrode and in close clearance therewith during the passage of said 'rn'oyable electrode through said chamber.

4. In a 'circiiit'brakerjwith pneumatic blow Out, a p ipa 'f x d cfi del ami b e c15 gated, lstfi l i hav a ont ct lfiJ mFe for moving; said nicvable .electrodeand its: contact end axially thereofawayifro m tow said fixed electrode, a'closed, blowro; t cham er having two spaced opposite, walls which are electrically insulating, said chamber being in; terposed in the path of the contact end ofsaid movable electrode between the extreme closed and open positions thereof, said charnber being provided, with two, nozzle openingsrespectively in said opposite walls thereof and alined axially in the pamiqr saidfflnovable electrode there} through and pIOVl dll'lg" a clearance around sai d movable elec ,od, saidmovable electrcde being tubular, a separatej-"elcngated ro d shaped auxiliary electrodefixedly carried by said chain: ber in a position within the bore of said tubular movable electrodeand in close-clearance therewith during the passage, ofsaid mcvable electrode through said chamber; saidauxiliary electrode having terminal, portions thereof. extending to each of said nozzileopenings. l c 5. In afcircuitbreakerwith pneumatic blowout, a principal fixedelectrode, a'movaue elongated electrode having acontactend, means for moving said movab "electrode and its contact end axially theredfilaway from and; toward said fixed electrode, a closed blow-out chamber haw. ing two "spaced oppostejwalls whichare elec,- trically insulatingps chamber being inter;- posed: in, the path, of the "conta'ctend, of said movableflelec rode between;- theextreine; closed andlope n positions thereofgsaid, chamber being provided with two nozzle openings respectively. in' said opl dsite walls} thereof and alined, axially in the pathof said"movablelelectr ode there-1 through .and providing ,a clearance around, said; movable electrode, saidmovable electrode being tubular, a separate elqngal d trod-shaped, auxiliary electrode, mounting means carried, bysa ld chamber and. carrying; said auxiliary electrode, for fixedly mounting'said auxiliary..electrode in.

saidchamber in a position intermediateandk tending between andl'spaced from said'opposltc walls thereof, and for mountingl said auxi l,iary

, e e de Within s-F qre' ta ai lw ubu ar-ewe .able electrode and in close clearance therewith during the passage of said --movable electrode through said chamber, said tubular movable electrode comprising means for permitting the passage therethrough of said mounting means as said movable electrode moves through said chamber.

.end axially thereof away from and toward said fixed electrode, a closed blow-out;chamber having two spaced opposite walls which are electrically insulating, said chamber being interposed the path of the contact end of said movableelectrode between the extreme closed and open positions thereof, said chamber being provided with two nozzle openings respectively in said opposite walls thereof and aligned axially inthe path of said movable electrod therethrough and providing a clearance aroundsaid movable electrode, said movable electrode being tubular, a separate elongated rod-shaped auxiliary electrode, mounting means carried by said chamber and carrying said auxiliary electrode for fixedly mounting said auxiliary electrode in said chamber in a position intermediate and extending between and spaced from said opposite walls thereof and for mounting said auxiliary electrode within the bore of said tubular movable electrode and in close clearance therewith during the passage of said movable electrode through said chamber, said tubular movable electrode comprising means for permitting the passage therethrough of said mounting means as said movable electrode moves through said chamber, said auxiliary electrode having terminal portions thereof extending substantially to each of said nozzle openings.

'7. In a circuit breaker with pneumatic blowout, a principal fixed electrode, a movable elongated electrode having a contact end, means for moving said movable electrode and its contact end axially thereof away from and toward said fixed electrode, a closed blow-out chamber having two spaced opposite walls which are electrically insulating, said chamber being interposed in the path of the contact end of said movable electrode between the extreme closed and open positions thereof, said chamber being provided with two nozzle openings respectively in said opposite walls thereof and alined axially in the path of said movable electrode therethrough and providing a clearance around said movable electrode, said movable electrode being tubular, a separate elongated rod-shaped auxiliary electrode, mounting means carried by said chamber and carryin said auxiliary electrode for fixedly mounting said auxiliary electrode therein and for mounting said auxiliary electrode in said chamber in a position intermediate and extending between and spaced from said opposite wall thereof and within the bore of said tubular movable electrode and in close clearance therewith during the passage of said movable electrode through said chamber, said tubular movable electrode comprising means for permitting the passage therethrough of said mounting means as said movable electrode moves through said chamber, and means for supplying gas under pressure to said chamber.

8. A circuit breaker according to claim 5, said nozzle openings being coaxial Venturi nozzles,

.and said auxiliary electrodabeing substantially coaxial with said nozzle openings.

9. A 'circuit breaker according to claim 5,'and an impedance connected between said auxiliary electrode and said principal fixed electrode,

10. A circuit breaker according to claim 5, and a resistance connected between said auxiliary electrode and said principal fixed electrode.

11. In a circuit breaker with pneumaticcblowr out, a principal fixed electrode, a movable elongated electrode having a contact end, means for moving said movable electrode and its, contact end axially thereof away from and toward said fixed electrode, a closed blow-out chamber interposed in the path of the contact end of said movable electrode between the extreme closed and open positions thereof, said chamber being provided with two nozzle openings respectively in opposite walls thereof and alined axially in the path of said movable electrode therethrough and providing a clearance around said movable electrode, said movable electrode being tubular, and a separate elongated rod-shaped auxiliary fixedly carried by said chamber in a position within the bore of said tubular movable electrode and in close clearance therewith during the passage of said movable electrode through said chamber, and gas inlet means mounted in the lateral wall of said chamber connecting said opposite walls thereof, and adapted to deliver into said chamber a blast of gas under pressure in a direction substantially perpendicular to the axis of said nozzles and to the path of said movable electrode through said chamber.

12. In a circuit breaker with pneumatic blowout, a principal fixed electrode, a movable elongated electrode having a contact end, means for moving said movable electrode and its contact end axially thereof away from and toward said fixed electrode, a closed blow-out chamber interposed in the path of the contact end of said movable electrode between the extreme closed and open positions thereof, said chamber being provided with two nozzle openings respectively in opposite walls thereof and alined axially in the path of said movable electrode therethrough and providing a clearance around said movable electrode, said movable electrode being tubular, a separate elongated rod-shaped auxiliary electrode, mounting means carried by said chamber for fixedly mounting said auxiliary electrode therein and for mounting said auxiliary electrode within the bore of said tubular movable electrode and in close clearance therewith during the passage of said movable electrode through said chamber, said tubular movable electrode comprising means for permitting the passage therethrough of said mounting means as said movable electrode moves through said chamber, and gas inlet means mounted in the lateral wall of said chamber connecting said opposite walls thereof, and adapted to deliver into said chamber a blast of gas under pressure in a direction substantially perpendicular to the axis of said nozzles and to the path of said movable electrode through said chamber.

13. In a circuit breaker with pneumatic blowout, a, principal fixed electrode, a movable elongated electrode having a contact end, means for moving said movable electrode and its contact end axially thereof away from and toward said fixed electrode, a closed blow-out chamber having two spaced opposite walls, said chamber bein provided in said opposite walls thereof "witl rcoaxial veriturr nozzle anemia-gs each awing a restricted throat and alinedaxially in the path of said movable electrode therethrough and providing a clearance aroundsaid movable electrode, said: movable electrode being tubular, a separate elongated rod-shaped auxiliary electrode, mounting means carried by said chamber and carry-ing said auxiliary electrode for fixedly mounting said auxiliary electrode in said chamber in a position intermediate and extending betweeri and spaced from said opposite walls thereof and formountingsaid auxiliary electrode withinthe bore of said tubular movable electrode and in close clearance therewith during the. passage of said movable electrode through saidchamber andsubstantially coaxial with said nozzle openings, said tubular movable electrode comprising means for permittingthe passage therethrough of. said mounting means as. said movable: electrode moves through said chamber,

said auxiliary electrode having terminal portions thereof: which extend: intosaid venturi. nozzle openings and respectively terminates-ubstantiall at the restricted throats thereof.

' REFERENCES GITED The following references are of record in the file of this patent:

UNITED STATES. PATENTS Number Name Date Re. 21,125 Ru-ppel June 20-, 1939 2,049,996 Clerc- Aug. 4, 1936 2,060,282 Clerc Nov; 10, 1986 FOREIGN PATENTS Number Country Date;

91,94z5, Sweden; Feb. 3, 1938 66 ,195 Germany ,..l.. Nov... 26, 1938 7 6 .1371; Enance; as, sr l l Jan. 10,; 1933 80939 2; France. l a .,.t.,...,l Dec. 19,. 193.6 33.31721: Eranca V July 25,. 193.8v 8 1427 June 30,. 1941 

